Typically, trim covers are attached to seat assemblies by J-strips which are sewn to an edge of the trim cover. The J-strip must be pulled down and flipped up underneath the edge of the seat frame and tucked in behind the frame for attaching the J-strip to the frame. Alternatively, the J-strip must be pulled beneath the frame assembly and attached to a wire within the interior of the frame support.
Such assemblies present significant assembly problems, which result in high assembly costs. Wrapping and tucking the J-strip beneath the seat frame can be a very difficult and time-consuming assembly operation. Also, extra trim cover material is needed in order to allow the J-strip to stretch sufficiently to reach a particular seat frame component to which it is attached.
Accordingly, it is desirable to provide a method of attaching a trim cover to a seat frame component in a manner in which the level of difficulty of assembly is reduced, and the amount of trim cover material required is reduced.
Another aspect of trim cover attachment is the formation of creases on the seat cover. Such creases are typically formed by providing a trench in a foam bun, and providing a wire in the bottom of the trench, and a wire attached to the edge of two trim components. The wires are then hog-ringed together within the trench to form the crease. This hog-ringing and wiring operation is a very expensive assembly operation. Alternatively, a T-shaped slot may be formed in the bun, and a flat plastic insert sewn to the edges of the trim cover, and the insert inserted into the T-shaped slot for securing the trim cover and forming the crease. This too is a difficult and expensive assembly operation.
Another method employs the sewing of two trim components together and wrapping a loop portion of a hook-and-loop fastener around the end portion and sewing the loop portion to the previously sewn trim edges. The hook portion of the hook-and-loop fastener is provided in the bottom of the trench for receiving the loop portion, which is attached to the trim covers for securing the trim cover edges within the trench to form the crease. This operation requires double-sewing, and the loop material which is wrapped around the previously sewn edges of the trim cover is relatively expensive.
Accordingly, it is desirable to provide a method of forming a trim cover crease in a seat cushion in which costs and assembly difficulty are reduced.